def ConvertShortCircuitIf(if_stmt: c_ast.If, parent: c_ast.Node, id_gen: common.UniqueId):
cond = if_stmt.cond
if isinstance(cond, c_ast.UnaryOp) and cond.op == "!":
# for a not not just swap the branches
if_stmt.cond = cond.expr
if_stmt.iffalse, if_stmt.iftrue = if_stmt.iftrue, if_stmt.iffalse
ConvertShortCircuitIf(if_stmt, parent, id_gen)
return
if not isinstance(cond, c_ast.BinaryOp):
return
if cond.op != "&&" and cond.op != "||":
return
labelnext = id_gen.next("branch")
if cond.op == "&&":
if_stmt2 = c_ast.If(cond.left, c_ast.Goto(labelnext), if_stmt.iffalse)
else:
assert cond.op == "||"
if_stmt2 = c_ast.If(cond.left, if_stmt.iftrue, c_ast.Goto(labelnext))
if_stmt.cond = cond.right
stmts = common.GetStatementList(parent)
# this is easy to fix but basically guaranteed after running IfTransform
assert stmts, parent
pos = stmts.index(if_stmt)
stmts[pos:pos + 1] = [if_stmt2, c_ast.Label(labelnext, c_ast.EmptyStatement()), if_stmt]
ConvertShortCircuitIf(if_stmt2, parent, id_gen)
ConvertShortCircuitIf(if_stmt, parent, id_gen)
def visit_Compound(self, node):
to_chain = []
for n in node.block_items:
if type(n) == c_ast.If:
to_chain.append(n)
self.generic_visit(n)
if len(to_chain) > 1:
for n in to_chain:
node.block_items.remove(n)
first_if = to_chain[0]
chained_if = c_ast.If(first_if.cond,
iftrue=first_if.iftrue,
iffalse=None)
prev_if = chained_if
node.block_items.append(chained_if)
for n in to_chain[1:-1]:
new_if = c_ast.If(n.cond, iftrue=n.iftrue, iffalse=None)
prev_if.iffalse = new_if
prev_if = new_if
last_if = to_chain[-1]
prev_if.iffalse = c_ast.If(last_if.cond,
iftrue=last_if.iftrue,
iffalse=None)
def insertTest(self,block,functionName,varVals,varTypes,timer):
#Fork call
cFork=c_ast.Assignment( lvalue=c_ast.ID(name='child_pid'), op='=', rvalue=c_ast.FuncCall( c_ast.ID(name='fork'), args=None))
#Child
if self.functype=='int' or self.functype=="bool":
printLeft=c_ast.Constant(type="char",value='"'+"%d" +'"')
elif self.functype=='float' or self.functype=='double':
printLeft=c_ast.Constant(type="char",value='"'+"%f" +'"')
else:
printLeft=c_ast.Constant(type="char",value='"'+"%d" +'"')
expressList = list(c_ast.Constant(type=varTypes[i],value=str(varVals[i])) for i in range(len(varVals)))
funcCall = c_ast.FuncCall(c_ast.ID(name=functionName),c_ast.ExprList(expressList))
expressList = [printLeft,funcCall]
funcCall = c_ast.FuncCall(c_ast.ID(name="printf"),c_ast.ExprList(expressList))
funcCall2 = c_ast.FuncCall(c_ast.ID(name="exit"),c_ast.ExprList([c_ast.Constant(type='int',value='0')]))
#Parent
cAlarm=c_ast.FuncCall( c_ast.ID(name='alarm'),c_ast.ExprList([c_ast.Constant(type='int',value=str(timer))]))
cWait=c_ast.FuncCall( c_ast.ID(name='wait'),c_ast.ExprList([c_ast.ID(name='0')]))
#IFs
if_false= c_ast.If( c_ast.BinaryOp(left=c_ast.ID(name='child_pid'),op='==',right= c_ast.Constant(type='int',value='0')), c_ast.Compound([funcCall,funcCall2]),iffalse=None)
if_ini=c_ast.If( c_ast.BinaryOp(left=c_ast.ID(name='child_pid'),op='>',right= c_ast.Constant(type='int',value='0')), c_ast.Compound([cAlarm,cWait]),iffalse=if_false)
block.body.block_items.insert(1,if_ini)
block.body.block_items.insert(1,cFork)
def insertTest(self,block,functionName,varVals,varTypes,timer,preOut,testId):
#Fork call
cFork=c_ast.Assignment( lvalue=c_ast.ID(name='child_pid'), op='=', rvalue=c_ast.FuncCall( c_ast.ID(name='fork'), args=None))
#Child
##stdout = freopen("out.txt", "w", stdout);
if self.functype=='int':
printLeft=c_ast.Constant(type="char",value='"'+"%d" +'"')
elif self.functype=='float' or self.functype=='double':
printLeft=c_ast.Constant(type="char",value='"'+"%f" +'"')
else:
printLeft=c_ast.Constant(type="char",value='"'+"%d" +'"')
fileOut=c_ast.Constant(type="char",value='"'+preOut +'.' +testId+".out.txt" +'"')
fileW=c_ast.Constant(type="char",value='"'+"w" +'"')
fileStdout=c_ast.ID(name='stdout')
expressList = [fileOut,fileW,fileStdout]
freopenC = c_ast.FuncCall(c_ast.ID(name="freopen"),c_ast.ExprList(expressList))
outReassign=c_ast.Assignment( lvalue=fileStdout, op='=', rvalue=freopenC)
##mainfake()
expressList = list(c_ast.Constant(type=varTypes[i],value=str(varVals[i])) for i in range(len(varVals)))
funcCall = c_ast.FuncCall(c_ast.ID(name=functionName),c_ast.ExprList(expressList))
expressList = [printLeft,funcCall]
funcCall = c_ast.FuncCall(c_ast.ID(name="printf"),c_ast.ExprList(expressList))
##exit(0)
funcCall2 = c_ast.FuncCall(c_ast.ID(name="exit"),c_ast.ExprList([c_ast.Constant(type='int',value='0')]))
#Parent
cAlarm=c_ast.FuncCall( c_ast.ID(name='alarm'),c_ast.ExprList([c_ast.Constant(type='int',value=str(timer))]))
cWait=c_ast.FuncCall( c_ast.ID(name='wait'),c_ast.ExprList([c_ast.ID(name='0')]))
#IFs
if_false= c_ast.If( c_ast.BinaryOp(left=c_ast.ID(name='child_pid'),op='==',right= c_ast.Constant(type='int',value='0')), c_ast.Compound([outReassign,funcCall,funcCall2]),iffalse=None)
if_ini=c_ast.If( c_ast.BinaryOp(left=c_ast.ID(name='child_pid'),op='>',right= c_ast.Constant(type='int',value='0')), c_ast.Compound([cAlarm,cWait]),iffalse=if_false)
block.body.block_items.insert(1,if_ini)
block.body.block_items.insert(1,cFork)
def visit_Assignment(self, node):
if self.inner_for:
self.remove_node()
if self.begin:
if not self.inner_begin_block:
self.inner_begin_block = c_ast.Compound([])
code = c_ast.If(c_ast.BinaryOp("==", self.inner_index, c_ast.Constant('int', '0')), self.inner_begin_block, None)
self.inner_for.stmt.block_items.insert(0, code)
self.inner_begin_block.block_items.append(node)
else:
if not self.inner_end_block:
self.inner_end_block = c_ast.Compound([])
code = c_ast.If(c_ast.BinaryOp("==", self.inner_index, c_ast.BinaryOp('-', self.inner_limit, c_ast.Constant('int', '1'))), self.inner_end_block, None)
self.inner_for.stmt.block_items.append(code)
self.inner_end_block.block_items.append(node)
def add_jumps(self, jump_map: Dict[str, c_ast.Node]):
for ghost_var, code in jump_map.items():
#print(ghost_var)
ghost_var_ast = c_ast.ID(ghost_var)
self.update_ast.block_items.append(
c_ast.If(ghost_var_ast, code, None))
def compile_node(lookup, decl_code, node):
code = []
stack = {}
inargs = []
pre = node.type + '_pre'
post = node.type + '_post'
compile_ast(lookup, stack, inargs, decl_code, code, pre)
for word in node.quotation:
compile_ast(lookup, stack, inargs, decl_code, code, word)
compile_ast(lookup, stack, inargs, decl_code, code, node.type)
call = code[-1]
end_stack = deepcopy(stack)
end_inargs = deepcopy(inargs)
end_code = []
compile_ast(lookup, end_stack, end_inargs, decl_code, end_code, post)
outargs = [a for args in end_stack.values() for a in args]
assign_results(outargs, end_code)
end_code.append(c_ast.Return(None))
end = c_ast.Compound(end_code)
condition = c_ast.If(call, end, None)
code[-1] = condition
compile_ast(lookup, stack, inargs, decl_code, code, post)
outargs = [a for args in stack.values() for a in args]
name = gensym(node.type)
fn = fndecl(name, inargs, outargs, code)
decl_code.append(fn)
lookup[name] = (inargs, outargs)
return name
def perm_refer_to_var(fn: ca.FuncDef, ast: ca.FileAST, indices: Indices,
region: Region, random: Random) -> bool:
"""Add `if (variable) {}` or `if (struct.member) {}` in a random place.
This will get optimized away but may affect regalloc."""
# Find expression to insert, searching within the randomization region.
cands: List[Expression] = [
expr for expr in get_block_expressions(fn.body, region)
if isinstance(expr, (ca.StructRef, ca.ID))
]
if not cands:
return False
expr = random.choice(cands)
if ast_util.is_effectful(expr):
return False
type: SimpleType = decayed_expr_type(expr, build_typemap(ast))
if isinstance(type, ca.TypeDecl) and isinstance(type.type,
(ca.Struct, ca.Union)):
expr = ca.UnaryOp("&", expr)
if random.choice([True, False]):
expr = ca.UnaryOp("!", expr)
# Insert it wherever -- possibly outside the randomization region, since regalloc
# can act at a distance. (Except before a declaration.)
ins_cands = get_insertion_points(fn, Region.unbounded())
ins_cands = [c for c in ins_cands if not isinstance(c[2], ca.Decl)]
if not ins_cands:
return False
cond = copy.deepcopy(expr)
stmt = ca.If(cond=cond, iftrue=ca.Compound(block_items=[]), iffalse=None)
tob, toi, _ = random.choice(ins_cands)
ast_util.insert_statement(tob, toi, stmt)
return True
def _build_handle_function(functions):
""" Wraps the switch statement in a function definition
"""
case_statement = _build_case(functions)
available_check = c_ast.If(
c_ast.BinaryOp(
'<', c_ast.FuncCall(
c_ast.ID('mailbox_available'),
c_ast.ExprList([c_ast.Constant('int', '2')])
),
c_ast.Constant('int', '4')
),
c_ast.Return(None),
None
)
handle_decl = c_ast.FuncDecl(
None, c_ast.TypeDecl('_handle_events', [],
c_ast.IdentifierType(['void'])),
)
command_decl = c_ast.Decl('command', [], [], [],
c_ast.TypeDecl('command', [],
c_ast.IdentifierType(['int'])),
[], [])
command_read = _generate_read('command')
body = c_ast.Compound([available_check,
command_decl,
command_read,
case_statement])
return c_ast.FuncDef(handle_decl, [], body)
def check_value(ast_tree, ext_index, bock_item_index, var_name, func_name):
Cast = c_ast.Cast(
c_ast.Typename(
None, [],
c_ast.PtrDecl([],
c_ast.TypeDecl(None, [],
c_ast.IdentifierType(['void'])))),
c_ast.ID(var_name))
func_call = c_ast.FuncCall(
c_ast.ID('check_value'),
c_ast.ExprList([
c_ast.UnaryOp('&', c_ast.ID('global_log')), Cast,
c_ast.Constant('string', '"' + var_name + '"'),
c_ast.Constant('string', '"' + func_name + '"'),
c_ast.Constant('int', str(len(var_name))),
c_ast.Constant('int', str(len(func_name)))
]))
new_node = c_ast.If(
c_ast.BinaryOp('==', func_call, c_ast.Constant('int', '0')),
c_ast.Compound([
c_ast.FuncCall(
c_ast.ID('printf'),
c_ast.ExprList([
c_ast.Constant('string', '"%s\\n"'),
c_ast.Constant('string', '"Attack Detected"')
])),
c_ast.FuncCall(c_ast.ID('exit'),
c_ast.ExprList([c_ast.Constant('int', '1')]))
]), None)
return merge_ast_tree(ast_tree, ext_index, bock_item_index, new_node,
"insert_before")
def optimize_new(graph, tabDeg, myWhile):
maxdeg = max_deg_of_list(tabDeg)
while_node = myWhile.node_while
peeling_deg = maxdeg + 1
if peeling_deg == 0:
myWhile.isOpt = True
return 0
initial_indices = []
tabDegs = []
nodelists = []
listIf = []
for i in range(peeling_deg):
nodelists.append([])
tabDegs.append([])
initial_indices.append([])
for i in range(len(tabDeg)):
for j in range(len(initial_indices)):
initial_indices[j].append(i)
for deg in tabDeg:
for i in range(len(tabDegs)):
tabDegs[i].append(deg)
for node in while_node.stmt.block_items:
for i in range(peeling_deg):
nodelists[i].append(node)
for i in range(maxdeg):
tbrm = []
for init_ind in initial_indices[i]:
if init_ind != -1:
if tabDeg[init_ind] == i + 1:
tbrm.append(init_ind)
for init_ind in tbrm:
curr_ind = initial_indices[i].index(init_ind)
(capture_tab, recover_tab) = captures(init_ind, myWhile.node_while,
tabDeg, graph)
for capture in capture_tab:
if capture[1] == -1 or capture[1] > i + 1:
for k in range(len(capture[0])):
nodelists[i].insert(curr_ind + 1, capture[0][k])
initial_indices[i].insert(curr_ind + 1, -1)
for j in range(i + 1, peeling_deg):
curr_ind = initial_indices[j].index(init_ind)
for (recover, deg) in recover_tab:
if deg == -1 or deg > j:
nodelists[j].insert(curr_ind + 1, recover)
initial_indices[j].insert(curr_ind + 1, -1)
nodelists[j].pop(curr_ind)
initial_indices[j].pop(curr_ind)
if DEBUG_LEVEL >= 3:
print(maxdeg, nodelists, initial_indices)
listIf.append(
c_ast.If(while_node.cond, c_ast.Compound(nodelists[i]), None))
listIf.append(
c_ast.While(while_node.cond, c_ast.Compound(nodelists[maxdeg]), None))
myWhile.parent[0].block_items.pop(myWhile.parent[1])
listIf.reverse()
for node in listIf:
myWhile.parent[0].block_items.insert(myWhile.parent[1], node)
myWhile.show()
myWhile.isOpt = True
def add_jump_guard(ast_to_guard, phase_var, round_var, label):
guarded_ast = c_ast.If(
c_ast.BinaryOp(
'&&', c_ast.BinaryOp('==', c_ast.ID(phase_var), c_ast.ID('PHASE')),
c_ast.BinaryOp('==', c_ast.ID(round_var), c_ast.ID(label))),
ast_to_guard, None)
return c_ast.Compound([guarded_ast])
def visit_If(self, n: ca.If) -> str:
n2 = n
if (n.iffalse and isinstance(n.iffalse, ca.Compound)
and n.iffalse.block_items and len(n.iffalse.block_items) == 1
and isinstance(n.iffalse.block_items[0], ca.If)):
n2 = ca.If(cond=n.cond,
iftrue=n.iftrue,
iffalse=n.iffalse.block_items[0])
return super().visit_If(n2) # type: ignore
def createOutputIf(self, expr):
expressList = [c_ast.Constant(type='int', value='0')]
funcCall = c_ast.FuncCall(c_ast.ID(name="assert"),
c_ast.ExprList(expressList))
if_all = c_ast.If(c_ast.BinaryOp(left=c_ast.ID(name='__out_var'),
op='==',
right=expr),
c_ast.Compound([funcCall]),
iffalse=None)
return (if_all)
def visit_While(self, node):
global global_trick_counter
if isinstance(self.current_parent, c_ast.Compound):
for i in xrange(len(self.current_parent.block_items)):
if self.current_parent.block_items[i] == node:
if global_do_trick:
global_trick_counter -= 1
if global_trick_counter == 0:
self.current_parent.block_items[i] = c_ast.If(node.cond, node.stmt, None, node.coord)
else:
global_trick_counter+= 1;
def test_nested_else_if_line_breaks(self):
generator = c_generator.CGenerator()
test_ast1 = c_ast.If(None, None, None)
test_ast2 = c_ast.If(None, None, c_ast.If(None, None, None))
test_ast3 = c_ast.If(None, None,
c_ast.If(None, None, c_ast.If(None, None, None)))
test_ast4 = c_ast.If(
None, c_ast.Compound([]),
c_ast.If(None, c_ast.Compound([]),
c_ast.If(None, c_ast.Compound([]), None)))
self.assertEqual(generator.visit(test_ast1), 'if ()\n \n')
self.assertEqual(generator.visit(test_ast2),
'if ()\n \nelse\n if ()\n \n')
self.assertEqual(generator.visit(test_ast3),
'if ()\n \nelse\n if ()\n \nelse\n if ()\n \n')
self.assertEqual(
generator.visit(test_ast4),
'if ()\n{\n}\nelse\n if ()\n{\n}\nelse\n if ()\n{\n}\n')
def ConvertWhileLoop(ast, id_gen: common.UniqueId):
def IsWhileLoop(node, _):
return isinstance(node, (c_ast.DoWhile, c_ast.While))
candidates = common.FindMatchingNodesPostOrder(ast, ast, IsWhileLoop)
for node, parent in candidates:
loop_label = id_gen.next("while")
test_label = loop_label + "_cond"
exit_label = loop_label + "_exit"
conditional = c_ast.If(node.cond, c_ast.Goto(loop_label), None)
block = [c_ast.Label(loop_label, c_ast.EmptyStatement()), node.stmt,
c_ast.Label(test_label, c_ast.EmptyStatement()), conditional,
c_ast.Label(exit_label, c_ast.EmptyStatement())]
if isinstance(node, c_ast.While):
block = [c_ast.Goto(test_label)] + block
common.ReplaceBreakAndContinue(node.stmt, node, test_label, exit_label)
common.ReplaceNode(parent, node, c_ast.Compound(block))
def replaceByPrint(self, ast):
expressList = [
c_ast.Constant(type='string', value='"[[REACHED]]"')
]
ifexpress = c_ast.Assignment(op="=",
lvalue=c_ast.ID(name="inst_flag"),
rvalue=c_ast.Constant(type='int',
value='1'))
self.funcCall.name = c_ast.ID(name="perror")
self.funcCall.args = c_ast.ExprList(expressList)
if_all = c_ast.If(c_ast.BinaryOp(left=c_ast.ID(name='inst_flag'),
op='==',
right=c_ast.Constant(type='int',
value='0')),
c_ast.Compound([self.funcCall, ifexpress]),
iffalse=None)
for position, inst_block in enumerate(self.inst_block):
inst_block[self.inst_pos[position]] = if_all
def addTestFunction(ast, expectedOutput, testFxn, initVars, initList):
varList = []
exprList = []
fxnName = ''
inFxn = False
listi = 0
for i in range(len(initVars)):
v = initVars[i]
if inFxn:
exprList.append(c_ast.Constant('int', initList[listi]))
listi += 1
if (')' in v):
inFxn = False
newVar = c_ast.FuncCall(c_ast.ID(fxnName), c_ast.ExprList(exprList))
varList.append(newVar)
exprList = []
else:
if ('(' in v):
fxnName = v[:v.index('(')]
if (v[v.index('(')+1] != ')'):
inFxn = True
exprList.append(c_ast.Constant('int', initList[listi]))
listi += 1
else:
newVar = c_ast.FuncCall(c_ast.ID(fxnName), c_ast.ExprList([]))
varList.append(newVar)
else:
newVar = c_ast.Assignment('=', c_ast.ID(v), c_ast.Constant('int', initList[listi]))
listi += 1
varList.append(newVar)
fxnDecl = c_ast.FuncDecl(None, c_ast.TypeDecl('klee_test_entry', [], c_ast.IdentifierType(['void'])))
fxnCall = c_ast.FuncCall(c_ast.ID(testFxn), c_ast.ExprList([]))
binaryOp = c_ast.BinaryOp('==', fxnCall, c_ast.Constant('int', expectedOutput))
ifFalse = c_ast.Compound([c_ast.FuncCall(c_ast.ID('klee_silent_exit'), c_ast.ExprList([c_ast.Constant('int', '0')]))])
ifTrue = c_ast.Compound([])
blockItems = []
for v in varList:
blockItems.append(v)
blockItems.append(c_ast.If(binaryOp, ifTrue, ifFalse))
fxnBody = c_ast.Compound(blockItems)
fxnNode = c_ast.FuncDef(fxnDecl, None, fxnBody)
ast.ext.append(fxnNode)
def convert(i):
if i >= n:
return
item = node.stmt.block_items[i]
# Item statement
stmt = (c_ast.Compound(item.stmts, coord=item.coord)
if isinstance(item.stmts, list) else item.stmts)
if i == (n - 1) and isinstance(item, c_ast.Default):
return stmt
if isinstance(item, c_ast.Case):
next = convert(i + 1)
ifcond = c_ast.BinaryOp('==', node.cond, item.expr,
coord=item.expr.coord)
return c_ast.If(ifcond, stmt, next, coord=item.expr.coord)
def ConvertForLoop(ast, id_gen: common.UniqueId):
candidates = common.FindMatchingNodesPostOrder(
ast, ast, lambda n, _: isinstance(n, c_ast.For))
for node, parent in candidates:
loop_label = id_gen.next("for")
next_label = loop_label + "_next"
test_label = loop_label + "_cond"
exit_label = loop_label + "_exit"
goto = c_ast.Goto(loop_label)
conditional = c_ast.If(node.cond, goto, None) if node.cond else goto
block = ExtractForInitStatements(node.init) + [
c_ast.Goto(test_label),
c_ast.Label(loop_label, c_ast.EmptyStatement()), node.stmt,
c_ast.Label(next_label, c_ast.EmptyStatement()),
node.next if node.next else c_ast.EmptyStatement(),
c_ast.Label(test_label, c_ast.EmptyStatement()), conditional,
c_ast.Label(exit_label, c_ast.EmptyStatement())
]
common.ReplaceBreakAndContinue(node.stmt, node, next_label, exit_label)
common.ReplaceNode(parent, node, c_ast.Compound(block))
def add_property(self,
property: c_ast.ExprList,
loop: c_ast.DoWhile or c_ast.While or c_ast.For,
slice: bool = True):
"""
Adds the given expression to the end of the given loop. Note that by doing this, any previous property becomes
unusable for our k-induction process.
:param expression: The expression to be added.
:param loop: The loop to add the property to.
:param slice: Whether the code was sliced by Frama-C or not.
"""
if hasattr(loop, "stmt") and type(loop.stmt) is c_ast.Compound:
if slice:
SliceFuncCallUpdater().visit(property)
property = self.join_expression_list("&&", property)
property_check = c_ast.If(
cond=property,
iftrue=c_ast.Compound(
[c_ast.FuncCall(c_ast.ID("__VERIFIER_error"), None)]),
iffalse=None)
loop.stmt.block_items.append(property_check)
def _get_assume_definition(self):
param_name = '__cond'
int_type = a.TypeDecl(param_name, [], a.IdentifierType(['int']))
param_list = a.ParamList(
[a.Decl(param_name, [], [], [], int_type, None, None)])
assume_type = a.TypeDecl('__VERIFIER_assume', [],
a.IdentifierType(['void']))
assume_func_decl = a.FuncDecl(param_list, assume_type)
assume_decl = a.Decl('__VERIFIER_assume', list(), list(), list(),
assume_func_decl, None, None)
exit_code = a.ExprList([a.Constant('int', '0')])
true_branch = a.Compound([a.FuncCall(a.ID('exit'), exit_code)])
false_branch = None
if_statement = a.If(a.UnaryOp('!', a.ID(param_name)), true_branch,
false_branch)
return_statement = a.Return(None)
body_items = [if_statement, return_statement]
assume_body = a.Compound(body_items)
return a.FuncDef(assume_decl, None, assume_body)
def cfg_path_to_ast(cfg):
"""Generates a AST from a CFG path (No FileAST support, it handles
FuncDecl, If, While and no compound objects).
Parameters
----------
cfg : ControlFlowGraph
"""
current_compound = c_ast.Compound([])
ast = current_compound
previous_compound = None
nodes = list(nx.topological_sort(cfg))
for n in nodes:
if type(n) in {c_ast.FuncDef, c_ast.While, c_ast.If}:
previous_compound = current_compound
current_compound = c_ast.Compound([])
if type(n) == c_ast.FuncDef:
inner_ast = c_ast.FuncDef(n.decl, n.param_decls,
current_compound)
elif type(n) == c_ast.While:
inner_ast = c_ast.While(n.cond, current_compound)
elif type(n) == c_ast.If:
inner_ast = c_ast.If(n.cond, current_compound, None)
previous_compound.block_items.append(inner_ast)
elif type(n) not in {
ControlFlowGraph.FuncDefEnd, ControlFlowGraph.IfEnd,
ControlFlowGraph.IfStart, ControlFlowGraph.WhileEnd
}:
current_compound.block_items.append(n)
return ast
def perm_ins_block(fn: ca.FuncDef, ast: ca.FileAST, indices: Indices,
region: Region, random: Random) -> bool:
"""Wrap a random range of statements within `if (1) { ... }` or
`do { ... } while(0)`. Control flow can have remote effects, so this
mostly ignores the region restriction."""
cands: List[Block] = []
def rec(block: Block) -> None:
cands.append(block)
for stmt in ast_util.get_block_stmts(block, False):
ast_util.for_nested_blocks(stmt, rec)
rec(fn.body)
block = random.choice(cands)
stmts = ast_util.get_block_stmts(block, True)
decl_count = 0
for stmt in stmts:
if isinstance(stmt, (ca.Decl, ca.Pragma)):
decl_count += 1
else:
break
lo = random.randrange(decl_count, len(stmts) + 1)
hi = random.randrange(decl_count, len(stmts) + 1)
if hi < lo:
lo, hi = hi, lo
new_block = ca.Compound(block_items=stmts[lo:hi])
if random.uniform(0, 1) < INS_BLOCK_DOWHILE_PROB and all(
region.contains_node(n) for n in stmts[lo:hi]):
cond = ca.Constant(type="int", value="0")
stmts[lo:hi] = [
ca.Pragma("sameline start"),
ca.DoWhile(cond=cond, stmt=new_block),
ca.Pragma("sameline end"),
]
else:
cond = ca.Constant(type="int", value="1")
stmts[lo:hi] = [ca.If(cond=cond, iftrue=new_block, iffalse=None)]
return True
def loop_peel(graph, list_deg, loop):
"""Peel the loop based on the maximum invariance degree"""
peeling_deg = max_deg_of_list(list_deg) + 1
if peeling_deg != 0: # if loop can be peeled
loop_node = loop.loop_node
parent_index = loop.parent[1] # index in the AST of the original loop
loop.parent[0].block_items.pop(parent_index) # remove the orignal loop from AST
commands = init_commands(peeling_deg,
loop_node.stmt.block_items) # initialize all the commands in the body of the loop
peel = [] # list of AST nodes for each peel
for i in range(peeling_deg):
peel_body = [] # list of commands for current peel
for (node, ind) in commands[i]:
# if the command can be peeled and has reached its peeling degree
if ind != -1 and list_deg[ind] == i + 1:
(capture_tab, recover_tab) = captures(ind, loop_node.stmt.block_items, list_deg, graph)
add_new_vars(commands, i, node, ind, peeling_deg, capture_tab, recover_tab)
peel_body.append(node)
# if its the last peel, add the body to a while statement with the same cond exp as the original while loop
if i == peeling_deg - 1:
peel.append(c_ast.While(loop_node.cond, c_ast.Compound(peel_body)))
else: # if not last peel, add the body to an if statement with the same cond exp as the original while loop
peel.append(c_ast.If(loop_node.cond, c_ast.Compound(peel_body), None))
# if the loop contains a break/contiue, wrap the entire peeled loop inside of a while loop with the same cond
# exp as the original
if check_break(loop_node.stmt):
peel = c_ast.While(loop_node.cond, c_ast.Compound(peel + [c_ast.Break()]), None)
loop.parent[0].block_items.insert(parent_index, peel)
else:
for i in peel: # add each peel to the modified AST
loop.parent[0].block_items.insert(parent_index, i)
parent_index = parent_index + 1
loop.isOpt = True
def new_if(cond, iftrue, iffalse):
return c_ast.If(cond, iftrue, iffalse)
def visit_FuncDef(self, node):
if (len(self.varList) < 1):
return
self.name = node.decl.name
# find the correct function name
if (self.name == self.function):
for idx, item in enumerate(node.body.block_items):
# find the return statement within that function
if (isinstance(item, c_ast.Return)):
returnStatement = item
for var in self.varList:
outOfScope = False
varArr = var.split(' ')
# make sure all variables of the expression are in-scope
for v in varArr:
if any(scopeV in v for scopeV in
self.outOfScopeVarList) and v != '':
outOfScope = True
break
if outOfScope:
# replace the return statement with a print of 0
node.body.block_items[idx] = c_ast.FuncCall(
c_ast.ID('fprintf'),
c_ast.ExprList([
c_ast.ID('stdout'),
c_ast.Constant('str', '"%d,"'),
c_ast.Constant('str', '"0"')
]))
break
else:
# replace the return statement with the first printed variable
node.body.block_items[idx] = c_ast.FuncCall(
c_ast.ID('fprintf'),
c_ast.ExprList([
c_ast.ID('stdout'),
c_ast.Constant('str', '"%d,"'),
c_ast.Constant('str', var)
]))
break
# add the remaining print statements
for var in self.varList[1:]:
# make sure all variables of the expression are in-scope
outOfScope = False
varArr = var.split(' ')
for v in varArr:
if any(scopeV in v
for scopeV in self.outOfScopeVarList) and v != '':
outOfScope = True
break
# print 0 if a variable is out of scope
if outOfScope:
node.body.block_items.append(
c_ast.FuncCall(
c_ast.ID('fprintf'),
c_ast.ExprList([
c_ast.ID('stdout'),
c_ast.Constant('str', '"%d,"'),
c_ast.Constant('str', '"0"')
])))
# print the expression if all variables are in scope
else:
if ('/' in var):
denom = var[var.index('/') + 1:]
binaryOp = c_ast.BinaryOp('==',
c_ast.Constant('str', denom),
c_ast.Constant('int', '0'))
ifTrue = c_ast.Compound([
c_ast.FuncCall(
c_ast.ID('fprintf'),
c_ast.ExprList([
c_ast.ID('stdout'),
c_ast.Constant('str', '"NaN,"')
]))
])
ifFalse = c_ast.Compound([
c_ast.FuncCall(
c_ast.ID('fprintf'),
c_ast.ExprList([
c_ast.ID('stdout'),
c_ast.Constant('str', '"%d,"'),
c_ast.Constant('str', var)
]))
])
node.body.block_items.append(
c_ast.If(binaryOp, ifTrue, ifFalse))
else:
node.body.block_items.append(
c_ast.FuncCall(
c_ast.ID('fprintf'),
c_ast.ExprList([
c_ast.ID('stdout'),
c_ast.Constant('str', '"%d,"'),
c_ast.Constant('str', var)
])))
# add a newline character and the original return statement at the end
node.body.block_items.append(
c_ast.FuncCall(
c_ast.ID('fprintf'),
c_ast.ExprList(
[c_ast.ID('stdout'),
c_ast.Constant('str', '"\\n"')])))
node.body.block_items.append(returnStatement)
def visit_If(self, n):
logger.debug('types(before branch): {}'.format(self._types))
logger.debug('Line {}: if({})'.format(n.coord.line, _code_generator.visit(n.cond)))
# update pc value updPC
before_pc = self._pc
self._pc = self._update_pc(self._pc, self._types, n.cond)
before_types = self._types.copy()
# corresponds to \Gamma_0 in paper
types_0 = self._types.copy()
# promote the shadow distances of the assigned variables to *
shadow_finder = _ExpressionFinder(lambda node: isinstance(node, c_ast.Assignment) and node.lvalue)
for assign_node in shadow_finder.visit(n):
if isinstance(assign_node.lvalue, c_ast.ID):
varname = assign_node.lvalue.name
elif isinstance(assign_node.lvalue, c_ast.ArrayRef):
varname = assign_node.lvalue.name.name
else:
raise NotImplementedError(
'Assign node lvalue type not supported {}'.format(type(assign_node.lvalue)))
align, shadow = types_0.get_distance(varname)
types_0.update_distance(varname, align, '*')
if self._pc and not before_pc:
self._types = types_0
# backup the current types before entering the true or false branch
cur_types = self._types.copy()
self._inserted_query_assumes.append([])
# add current condition for simplification
self._types.apply(n.cond, True)
# to be used in if branch transformation assert(e^aligned);
aligned_true_cond = _ExpressionReplacer(self._types, True).visit(
copy.deepcopy(n.cond))
self.visit(n.iftrue)
true_types = self._types
logger.debug('types(true branch): {}'.format(true_types))
true_assumes = self._inserted_query_assumes.pop()
self._inserted_query_assumes.append([])
# revert current types back to enter the false branch
self._types = cur_types
self._types.apply(n.cond, False)
if n.iffalse:
logger.debug('Line: {} else'.format(n.iffalse.coord.line))
self.visit(n.iffalse)
# to be used in else branch transformation assert(not (e^aligned));
aligned_false_cond = _ExpressionReplacer(self._types, True).visit(copy.deepcopy(n.cond))
logger.debug('types(false branch): {}'.format(self._types))
false_types = self._types.copy()
self._types.merge(true_types)
logger.debug('types(after merge): {}'.format(self._types))
false_assumes = self._inserted_query_assumes.pop()
exp_checker = _ExpressionFinder(
lambda node: isinstance(node, c_ast.ArrayRef) and '__SHADOWDP_' in node.name.name and
self._parameters[2] in node.name.name)
if self._loop_level == 0:
if self._pc and not before_pc:
# insert c_s
c_s = self._instrument(before_types, types_0, before_pc)
if_index = self._parents[n].block_items.index(n)
self._parents[n].block_items[if_index:if_index] = c_s
for statement in c_s:
self._inserted.add(statement)
self._inserted.add(n)
# insert c_shadow
shadow_cond = _ExpressionReplacer(types_0, False).visit(
copy.deepcopy(n.cond))
shadow_branch = c_ast.If(cond=shadow_cond,
iftrue=c_ast.Compound(
block_items=copy.deepcopy(n.iftrue.block_items)),
iffalse=c_ast.Compound(
block_items=copy.deepcopy(n.iffalse.block_items)) if n.iffalse else None)
shadow_branch_generator = _ShadowBranchGenerator(
{name for name, (_, shadow) in types_0.variables() if shadow == '*'},
types_0)
shadow_branch_generator.visit(shadow_branch)
if_index = self._parents[n].block_items.index(n)
self._parents[n].block_items.insert(if_index + 1, shadow_branch)
self._inserted.add(shadow_branch)
# insert assume functions before the shadow branch
for query_node in exp_checker.visit(shadow_cond):
assume_functions = self._assume_query(query_node)
index = self._parents[n].block_items.index(n) + 1
self._parents[n].block_items[index:index] = assume_functions
for assume_function in assume_functions:
self._inserted.add(assume_function)
# create else branch if doesn't exist
n.iffalse = n.iffalse if n.iffalse else c_ast.Compound(block_items=[])
# insert assert and assume functions to corresponding branch
for aligned_cond in (aligned_true_cond, aligned_false_cond):
block_node = n.iftrue if aligned_cond is aligned_true_cond else n.iffalse
# insert the assertion
assert_body = c_ast.ExprList(exprs=[aligned_cond]) if aligned_cond is aligned_true_cond else \
c_ast.UnaryOp(op='!', expr=c_ast.ExprList(exprs=[aligned_cond]))
block_node.block_items.insert(0, c_ast.FuncCall(name=c_ast.ID(self._func_map['assert']),
args=assert_body))
# if the expression contains `query` variable,
# add assume functions on __SHADOWDP_ALIGNED_DISTANCE_query and __SHADOWDP_SHADOW_DISTANCE_query
inserted = true_assumes if aligned_cond is aligned_true_cond else false_assumes
self._inserted_query_assumes.append(inserted)
for query_node in exp_checker.visit(aligned_cond):
assume_functions = self._assume_query(query_node)
block_node.block_items[0:0] = assume_functions
self._inserted_query_assumes.pop()
# instrument statements for updating aligned or shadow distance variables (Instrumentation rule)
for types in (true_types, false_types):
block_node = n.iftrue if types is true_types else n.iffalse
inserted = true_assumes if types is true_types else false_assumes
self._inserted_query_assumes.append(inserted)
instruments = self._instrument(types, self._types, self._pc)
block_node.block_items.extend(instruments)
for instrument in instruments:
self._inserted.add(instrument)
self._inserted_query_assumes.pop()
self._pc = before_pc
def _assume_query(self, query_node):
""" instrument assume functions of query input (sensitivity guarantee) """
assume_functions = []
shadow_distance_node = copy.deepcopy(query_node)
align_distance_node = copy.deepcopy(query_node)
regex = re.compile(r'__SHADOWDP_[A-Z]+_DISTANCE_([_a-zA-Z][a-zA-Z0-9\[\]]*)')
align_distance_node.name.name = regex.sub(r'__SHADOWDP_ALIGNED_DISTANCE_\g<1>', query_node.name.name)
shadow_distance_node.name.name = regex.sub(r'__SHADOWDP_SHADOW_DISTANCE_\g<1>', query_node.name.name)
common_assume = [
c_ast.FuncCall(
name=c_ast.ID(self._func_map['assume']),
args=c_ast.ExprList(exprs=[c_ast.BinaryOp(op='<=',
left=align_distance_node,
right=c_ast.Constant('int', '1'))])),
c_ast.FuncCall(
name=c_ast.ID(self._func_map['assume']),
args=c_ast.ExprList(exprs=[c_ast.BinaryOp(op='>=',
left=align_distance_node,
right=c_ast.Constant('int', '-1'))])),
c_ast.FuncCall(
name=c_ast.ID(self._func_map['assume']),
args=c_ast.ExprList(exprs=[c_ast.BinaryOp(op='==',
left=shadow_distance_node,
right=align_distance_node)]))
]
# insert following statements:
# if (i == __SHADOWDP_index) {
# assume(__SHADOWDP_ALIGNED_DISTANCE_q[i] >= -1); assume(__SHADOWDP_ALIGNED_DISTANCE_q[i] <= 1);
# assume(__SHADOWDP_SHADOW_DISTANCE_q[i] == __SHADOWDP_ALIGNED_DISTANCE_q[i]);
# }
# else {
# assume(__SHADOWDP_ALIGNED_DISTANCE_q[i] == 0);
# assume(__SHADOWDP_SHADOW_DISTANCE_q[i] == __SHADOWDP_ALIGNED_DISTANCE_q[i]);
# }
if self._one_differ:
if_block = c_ast.If(cond=c_ast.BinaryOp('==',
left=query_node.subscript,
right=c_ast.ID(name='__SHADOWDP_index')),
iftrue=c_ast.Compound(block_items=[]),
iffalse=c_ast.Compound(block_items=[]))
if_block.iftrue.block_items = common_assume
if_block.iffalse.block_items = [
c_ast.FuncCall(
name=c_ast.ID(self._func_map['assume']),
args=c_ast.ExprList(exprs=[c_ast.BinaryOp(op='==',
left=shadow_distance_node,
right=align_distance_node)])),
c_ast.FuncCall(
name=c_ast.ID(self._func_map['assume']),
args=c_ast.ExprList(exprs=[c_ast.BinaryOp(op='==',
left=align_distance_node,
right=c_ast.Constant('int', '0'))]))
]
assume_functions.append(if_block)
# insert following statements:
# assume(__SHADOWDP_ALIGNED_DISTANCE_q[i] >= -1); assume(__SHADOWDP_ALIGNED_DISTANCE_q[i] <= 1);
# assume(__SHADOWDP_SHADOW_DISTANCE_q[i] == __SHADOWDP_ALIGNED_DISTANCE_q[i]);
else:
assume_functions = common_assume
# if assume function has already been inserted in this scope
for inserted in self._inserted_query_assumes[-1]:
if is_node_equal(assume_functions, inserted):
return []
self._inserted_query_assumes[-1].append(assume_functions)
return assume_functions